1. Field of the Invention
This invention relates to a so-called push-open type storage device, and particularly to a storing device furnished with a safety function, to be installed as in an instrument panel of an automobile.
2. Description of the Prior Art
Generally, a conventional push-open type storing device of this sort comprises a storing box openably supported in a housing which is provided on an instrument panel side and constantly kept biased in the opening direction thereof by virtue of the pressure of a spring, a cam member provided therein with a cam groove which has an inlet mouth, a locking part and an outlet mouth and rotatably set in place on the housing side, and a pin member adapted to move inside the cam groove of the cam member and set in place on the storing box side. Owing to the construction thereof described above, the conventional device allows the storing box to lock itself in the shutting position thereof inside the housing in spite of the biasing spring pressure by bringing the pin member into engagement with the locking part of the cam groove and then allows the storing box in the locked state to move automatically in the opening direction through the opening part of the housing by pushing the storing box farther inside the housing to thereby release the pin member from the engagement with the locking part of the cam groove.
As illustrated in FIG. 7 and FIG. 8, a cam member 21 used in the conventional device is rotatably kept in place on a shaft 27 on the housing side through a torsion spring 28 and is constantly kept biased in one prescribed direction by the pressure of the torsion spring 28 until it is restrained by a restraining wall 29. Specifically, this cam member 21 is so constructed as to have integrally incorporated therein on one edge side thereof defining its cam groove 22 a locking part 24 and an outlet mouth 25 which are in an extremely approximated state and on the other edge side thereof opposite the aforementioned one edge side a guide wall 26 for a pin member P.
The cam member 21 constructed as described above has been developed exclusively for the purpose of guiding the pin member P in the direction of the outlet mouth 25 by virtue of the function of an inner edge 26a of the guide wall 26. Therefore, the guide wall 26 is so formed that the leading terminal thereof will protrude outward as compared with the position of the locking part 24, namely thrust out in the direction of an inlet mouth 23 of the cam groove 22. In other words, the locking part 24 for securing the pin member P is disposed on the inner side from the leading terminal of the guide wall
When the storing box is pushed into the housing, therefore, the pin member P disposed on the rear terminal side of the storing box collides against an outer guide surface 21a of the cam member 21, rotates the cam member 21 and reaches the inlet mouth 23 of the cam groove 22. When the pin member P collides against the guide wall 26 of the cam member 21, then the cam member 21 is slightly rotated in the biasing direction by the pressure of the torsion spring 28 and the pin member P is guided into the cam groove 22 and, as a result, the storing box is retracted by the biasing spring pressure. Thus, the pin member is automatically brought into engagement with the locking part 24 positioned inside the cam groove 22 and locks the storing box infallibly at the shut position inside the housing in spite of the biasing spring pressure as illustrated in FIG. 7.
When the storing box in the locked state is pushed farther into the housing, the pin member P departs from the locking part 24 of the cam groove 22, collides against the inner edge 26a of the guide wall 26 and allows the cam member 21 to be rotated further in the biasing direction (the unlocking direction) as illustrated in FIG. 8. When the storing box is subsequently relieved of this pushing motion, the pin member P is guided in the direction of the outlet mouth 25 of the cam groove 22 and enabled to depart automatically from the cam groove 22 of the cam member 21 and, as a result, the storing box is caused by virtue of the biasing spring pressure to move automatically from the opening part of the housing in the opening direction.
When the storing box which is locked in the shut position thereof with the pin member P kept in engagement with the locking part 24 is exposed to a large inertial force to be generated when the automobile is brought to a sudden stop because of collision or application of brakes, the storing box is moved in the same direction as the direction of inertia. At this time, the pin member P, synchronously with the motion of the storing box and in the same manner as in the open state illustrated in FIG. 8, departs from the locking part 24 and allows the cam member 21 to rotate in the unlocking direction. This fact opens up the possibility of the storing box being accidentally moved through the opening part of the housing in the opening direction by the biasing spring pressure and inflicting damage on the occupant of the automobile.
In recent years, therefore, the practice of furnishing the push-open type storing device in particular with a safety function for the prevention of this accident has become an obligatory measure.
Such a storing device furnished with a safety function is disclosed in Japanese Utility Model Public Disclosure No. 2-25332, for example.
This prior art storing device furnished with the safety function, though omitted from illustration herein, comprises a guide piece integrally extended from the rear terminal part of a cam member similar in shape to the conventional cam member 21 described above, an inertia-responding member slidably disposed on the guide piece, a tension spring adapted to draw the inertia-responding member in the direction of the rear terminal part of the cam member, and a lock cylinder adapted to allow entry therein of the terminal part of the inertia-responding member and formed in the relevant part of the housing.
Therefore, the prior art device is used similarly in the normal service to the conventional push-open type storing device. When the storing box which is kept locked in its shut position is exposed to a large inertial force as when the automobile is brought to a sudden stop by collision or application of brakes, therefore, this device operates so that the terminal part of the inertia-responding member disposed on the guide piece of the cam member thrusts into the lock cylinder in spite of the drawing force of the tension spring and inhibits the cam member from rotating in the unlocking direction and, as a result, prevents the storing box from thrusting out of the housing through the opening part thereof.
The prior art storing device furnished with the safety function not only necessitates incorporation therein as an extra component of the inertia-responding member separately of the cam member but also requires the guide piece to be integrally extended from the rear terminal part of the cam member, the inertia-responding member to be disposed on the guide piece as vested with the drawing force of the tension spring, and the lock cylinder to be formed separately on the housing side as adapted to allow entry therein of the terminal part of the inertia-responding member. This construction, therefore, automatically entails an increase in the number of component parts and an uncalled-for addition to the cost, complexity, and size of the storing device and suffers consequently from the serious problem of increasing the number of works involved in the assembly and jeopardizing the efficiency of the operation of assembly.
The prior art storing device further has the possibility of lacking reliability of performance because of the undeniable phenomenon that when the unlocking stroke of the storing box is short, the cam member rotates in the unlocking direction and accidentally thrusts the storing box outside before the inertia-responding member begins to move on the guide piece.
In the light of the problems encountered by the prior art storing device furnished with the safety function and intended for use in an automobile as described above, the major object of this invention is to provide a storing device for use in an automobile which infallibly manifests a safety function without necessitating use of an independent part intended exclusively for that purpose.